Dental tool-holder.



Patented Nov. Il, i902.

C. A. LUNDBERG. DENTAL Tool. HOLDER.

(Application led Jan. 13, 1902.)

(Nolodal.)

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CHARLES A. LUNDBERG, OF NEV YORK, N. Y., ASSIGNOR TO TI-IE CONSOLI- DATED DENTAL MANUFACTURING COMPANY, OF NEV YORK, N. Y., A

CORPORATION OF NEW YORK.

DENTAL TOOL-HOLDER.

SPECIFICATION forming part of Letters atent No. 713,319, dated November 11, 1902.

Application filed January 13J 1902. Serial No. 89,400. (No model.)

.To @ZZ whom. it' pta/y con/cern:

Beit known that I, CHARLES A. LUNDBERG., a citizen of the United States, and a resident of the borough of Bronx, in the city and State 5 of New York, have invented a new and useful Improvement in Dental Tool-Holders, of which the following is a specification.

My invention relates to an improvement in dental tool-holders, and has for its object to 1o provide a holder for use in connection with dental engines in which the several parts are so constructed and combined as to produce a very strong and effective device which may be accurately adjusted and in which the tool i5 is locked within its chuck by the forward movement of the locking and releasing slide rather than by a rearward movement of the same, as has heretofore been common.

A practical embodiment of my invention is 2o represented in the accompanying drawings,

in which- Figure 1 is an exterior View of the holder with a dental tool clamped therein. Fig. 2 is a longitudinal central section through the z5 same. Eig. 3 is an exterior view of the combined chuck and spindle comprising the rotary portion of the holder. Fig. 4 is a transverse section taken in the plane of the line A A of Fig. 2. Fig. 5 is a transverse section 3o taken in the plane of the line B B of Fig. 2. Fig. 6 is a detail view, partially in section, showing the position of the slide and the parts which it operates when the slide is at the limit of its backward movement for re- 35 leasing the tool from vthe chuck. Fig. 7 is a side view of the intermediate rod. Fig. 8 is a side view of the locking and releasing dog. Fig. 9 is alongitudinal central section through the dog-carrying bar; and Fig. 10 is a longi- 4o tudinal central section through the inner or cam section of the locking and releasing slide, showing a modified form of cam.

The combined spindle and chuck has a tubular forward section 1 and a tubular rear 45 section 2, to which the forward section is removably secured in the present instance by means of a screw-threaded engagement therewith. This rear section 2 has projected rearwardly therefrom the reduced portion 3, to

which the flexible shaft (not shown herein) 5o of the dental engine may be attached.

The forward tubular section 1 has located therein a split sleeve f1, fitted to receive the shank of the dental tool 5. The rear end of the split sleeve 4 is beveled, which bevel is 55 engaged by the beveled forward end of a hollow solid sleeve 6, so that when the sleeve G is pushed forward it will close the split sleeve 4. and clamp the tool 5 therein. A bar 7 is fitted to the bore of the rear tubular section 6o 2 so as to slide freely therein. An intermediate rod 8 is interposed between the bar 7 and the sleeve 6, which rod is provided with a reduced forward end 9, forming a shoulder 10. This reduced end 9 is fitted to the bore 65 of the sleeve 6, and one or more washers 11 may be inserted between the shoulder 10 and the rear end of the sleeve 6, so as to accurately adjust the distance between the rear end of the sleeve 6 and the front end of the bar 7. 7o The bar 7 is provided with an elongated slot 12 therethrough for receivingtherein the tailpiece 13 of a spring-actuated dog, the head 14. of which is fitted to be interposed between the rear end of the bar 7 and the bottom of 75 the bore within the rear section 2 of the combined spindle and chuck. The shape of the slot 12 is such that a bridge 15 is formed at the inner end of the bar, against which the forward face of the head 14 of the dog presses, 8o while the rear face of the said head presses against the bottom of the bore in the rear section 2. Elongated slots 16 and 17 are formed through the opposite walls of the rear tubular section 2 for permitting the insertion and 85 operation of the dog, as will be hereinafter set forth. The inner tubular section of the slide for operating the dog is denoted by 1S, and it is provided along its bore with a longitudinal feather 19, which is fitted to slide 9o along within the elongated Vslot 17in the section 2 and also projects a slight distance into the interior elongated slot 12 in the dog-carrying bar 7. The front end of this feather is beveled, as shown at 20, to form a cam for 95 operating the tailpiece 13 of the dog.

The handpiece 21 may be of any suitable shape and size for effectually concealing the combined chuck and spindle. This handpiece 21 is provided with an elongated slot 22, extended lengthwise through one of its Walls adjacent to the inner section 18 of the slide. The outer section 23 of the slide is loosely iitted to the exterior of the casing over the slot 22 therein.

The connection between the outer section, which is held against rotary movement, and the inner section of the slide, which rotates with the combined chuck and spindle, is as follows: The inner section of the slide is provided with an annular groove 24, within which a nut 25 is located in position to receive a screw 26, carried by the outer section 23 of the slide. This nut 25 is loosely fitted within the grove 24, so as to permit the inner section to rotate with the spindle without rotating the outer section also.

The combined chuck and spindle is removably secured within the handpiece 21 as follows: A hollow eXteriorly-screW-threaded plug 27 embraces the reduced portion 3 of the spindle and has a screw-threaded engagement at its forward end with the rear end of theY said handpiece 2l. The screw-threaded periphery of the plug 27 is intercepted by an annular groove 28, which is engaged by a setscrew 29, carried by a nut 30, which also has aiscrew-threaded engagement with the said plug. By this arrangement the nut 30 may be adjusted a limited distance along the plug 27j and then locked in position by setting the screw .29v home. They plug may then be screwed into the rear endV of the casing 21 untiljthe nut 30 abuts against the end of the casing.

The operation of the device is as follows: supposing the parts to be in the position shownin Fig. 6, with the slide at the limit of its rearward movement, the tailpiece v13 of the dogV is dropped beyond the end of the inner sectionl of the slide and its head is in a position topermit the rear end of the bar v7 to be brought in close proximity to the bottom of the bore in the rear section 2 of the combined chuck and spindle, After a= tool has been inserted within the split sleeve 4 the slide is movedforward, thus causing the cam 2 0 on the front end of the feather 19 of the inner section of the slide to force the tailpiece 13 of the dog inwardly, thus rocking the head 14: for forcing the rear end of the bar 7 away from the bottom of the bore in the rear section of the combined chuck and spin dle. The movement of the slide is suflicient to cause the tailpiece 13 to travel along the feather, and thus hold the tailpiece in its position under tension, owing to a slight spring inthe tailpiece, This forward movement of the bar 7 will force the intermediate rod 8 forward, and it inturn will move the solid sleeve 6 forward for bringing the split sleeve 4 into clamping engagement with the tool 5.y

The construction as above set forth is eX- tremely strong and durable and one which is not liable to get out of order. Furthermore,

the locking of the tool in position by the forward movement of the slidev prevents any unintentional releasing of the tool when pressure is applied thereto.

Where the tool was locked by the rear movement of the slide the operator had to be careful not to exert a forward pressure on the slide, as that would tend to release the tool.

In Fig. 10 I have shown a inodied form of inner section of the slide, in which a shoulder 31 is provided at the rear end ot' the cambevel 20, so as to cause the tailpiece of the dog to engage the shoulder when the slide is moved into position to clamp the tool, thus locking the dog in position.

What I claim is- 1. A tool-holderfordental engines comprising a handpiece, a hollow combined chuck and spindle, a split sleeve therein adapted to receive the tool, adog-retaining. bar located in the combined chuck` andspindle foroperating the split sleeve, a rocking dog located within the dog-retaining bar and engaging the bar and combined chuck` and spindle for forcing the bar forward to cause it to operate the split sleeve to clamp the tool and afslide for operating the dog, substantially asset forth.

2. A tool-holder for dental engines comprising a handpiece, a hollow combined chuck and spindle, a split sleeve therein adapted to receive the tool, a dog-retainingbar located in the combined chuck and spindle foi-.operating the split sleeve, a rocking dog having vits head interposed between the rear end of the bar and the closed endof. the hollow combined chuck and spindle for forcing the bar forward to cause it to operate the split sleeve to clamp the tool and a slide for operating `the dog,- substantially as set forth.

3. A tool-holder for dental engines comprising a handpiece, a hollow combined chuck and spindle closedat one end and having therein a split sleeve for receiving the tool, a dogretaining bar for operating the split sleeve, means for positively sliding the bar forward consisting of a rocking dog having its head engaged with the rear end of the bar and the closed end of the combined chuck and spindle and a slide for rocking the dog comprising an inner cam-section having an annular groove therein, a nut iittedvtosaid groove, an outer section carried by the handpiece and a screw passing through the casing and connecting the outer section with the nut, substantially as set forth.

4. A tool-holder for dental engines comprising a handpiece, a hollow combined chuck and spindle closed at one endI and having therein a split sleeve for receiving the tool, a dog-retaining bar having an elongated slot therein, the said combined chuck and spindle having an elongated slot therein in alinement with the slot in said bar, a dog havingits head engaging the rear end of the bar and the closed end of the combined chuck and spindle and its tailpiece located in ysaid slot IOO IIO

in the dog-retaining bar and a slide having a feather arranged to travel along the slot in the combined chuck and spindle in engagement with the tailpieee of the dog, the said feather having a 0am at its forward end for rocking the dog to slide the bar forward for operating the split sleeve, substantially as set forth.

5. A tool-holder for dental engines com prising a handpieoe, a hollow combined chuck and spindle closed at one end and having therein a split sleeve for receiving the tool, a chuck-retaining bar having an elongated slot therein and the said combined chuck and spindle having angelongated slot therein in alinement with the slot in the said bar, a dog having its head engaging the rear end of the bar and the closed end of the combined chuck and spindle and its tailpiece located in the said slot in the dog-retaining bar and a slide having a feather arranged to travel along the slot in the combined chuck and spindle in engagement with the tailpieee of the dog, the said feather having a earn at its forward end for rocking the dog to slide the bar forward for operating the split sleeve and a shoulder at the end of the cam for engaging the tailpieoe to prevent the unintentional release of the dog, substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed my name, in presence of tWo Witnesses, this 2d day of January, 1902.

CHARLES A. LUNDBERG.

Witnesses:

GEORGE J. BULTMAN, MICHAEL J. MURRAY. 

